U.S. patent application number 10/415399 was filed with the patent office on 2004-04-22 for method for making an air filter.
Invention is credited to Cocconi, Carlo.
Application Number | 20040074215 10/415399 |
Document ID | / |
Family ID | 32095257 |
Filed Date | 2004-04-22 |
United States Patent
Application |
20040074215 |
Kind Code |
A1 |
Cocconi, Carlo |
April 22, 2004 |
Method for making an air filter
Abstract
A method for forming an air filter (1, 5) comprising a filter
element (2) and at least one seal gasket (3) rigidly secured to
said filter element, in which in order to form said gasket (3) a
plastic material is cast in a mould (4, 8, 11), and in order to
rigidly secure said filter element (2) to said gasket (3) in a
sealed manner the filter element is associated with said plastic
material while this is in said mould (4, 8, 11) and the curing of
said plastic material is still at least partially in progress,
wherein for forming each filter its own dedicated mould (4, 8, 11)
is used, the mould being maintained removably associated with said
gasket (3) after termination of the filter forming process.
Inventors: |
Cocconi, Carlo; (Correggio,
IT) |
Correspondence
Address: |
UNION CARBIDE CHEMICALS AND PLASTICDS TECHNOLOGY
CORPORATION
P.O. BOX 1967
MIDLAND
MI
48674
US
|
Family ID: |
32095257 |
Appl. No.: |
10/415399 |
Filed: |
July 7, 2003 |
PCT Filed: |
November 5, 2001 |
PCT NO: |
PCT/US01/47323 |
Current U.S.
Class: |
55/502 |
Current CPC
Class: |
B01D 46/0001
20130101 |
Class at
Publication: |
055/502 |
International
Class: |
B01D 046/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 10, 2000 |
IT |
M 12000A002435 |
Claims
What is claimed is:
1. A method for forming an air filter (1, 5) comprising a filter
element (2) and at least one seal gasket (3) rigidly secured to
said filter element, in which in order to form said gasket (3) a
plastic material is cast in a mould (4, 8, 11), and in order to
rigidly secure said filter element (2) to said gasket (3) in a
sealed manner the filter element is associated with said plastic
material while this is in said mould (4, 8, 11) and the curing of
said plastic material is still at least partially in progress,
characterised by using for forming each filter its own dedicated
mould (4, 8, 11) and maintaining the mould removably associated
with said gasket (3) after termination of the filter forming
process.
2. A method as claimed in claim 1, characterised by using the mould
(8) as packaging for the filter.
3. A method as claimed in claim 1, characterised by using the mould
(11) as a filter holder (11, 12) to be directly associated with the
device using the filter.
4. A method as claimed in claim 1, characterised by causing the
plastic material curing process to take place within the mould (4,
8, 11) without subjecting it to thermal treatment to accelerate
said curing.
5. A method as claimed in claim 1, characterised by using mutually
incompatible plastic materials for forming the mould (4, 8, 11) for
the gasket (3), and for the gasket (3) itself.
6. A method as claimed in claim 5, characterised by using
polystyrene, polypropylene, polyethylene, teflon or mixtures of
these plastic materials, for forming the mould (4, 8, 11) and the
gasket.
7. An air filter comprising a filter element (2) and at least one
seal gasket (3) rigidly secured to said filter element (2), in
which in order to form said gasket (3) a plastic material is cast
in a mould (4, 8, 11), and in order to rigidly secure said filter
element (2) to said gasket (3) in a sealed manner the filter
element is associated with said plastic material while this is in
said mould and the curing of said plastic material is still at
least partially in progress, characterised in that each filter
comprises its own mould (4, 8, 11), which remains removably secured
to said gasket (3) on termination of curing of said plastic
material.
8. A filter as claimed in claim 7, characterised in that the mould
(8) is shaped such as to also act as packaging for the filter.
9. A filter as claimed in claim 7, characterised in that the mould
(11) is formed in such a manner as to also act as a filter holder,
to be directly associated with the device using the filter.
10. A filter as claimed in claim 7, characterised in that the mould
(4, 8, 11) is formed of a plastic material incompatible with the
plastic material of the gasket (3).
11. A filter as claimed in claim 7, characterised in that the mould
(4, 8, 11) is of disposable type.
12. A filter as claimed in claim 7, characterised in that the mould
(8, 11) comprises a cover (9, 12) arranged to maintain the filter
element (2) in a desired position and/or to shape a portion of the
gasket (3) in a desired manner.
13. A filter as claimed in claim 7, characterised in that the cover
(9, 12) is rigidly or removably secured to the mould (8, 11).
14. A filter as claimed in claim 7, characterised in that the mould
(11) comprises a recessed surround (6) into which to pour the
plastic material to form the gasket (3) and, inwards of said
surround, a flat support surface (3) for the filter element
(2).
15. A filter as claimed in claim 14, characterised in that the flat
support surface (7) is provided at a lower height than the free
edge (6A) of the recessed surround (6) and has smaller dimensions
than that face (2A) of the filter element (2) which rests on said
surface (7).
16. A mould for forming an air filter (1, 5) comprising a filter
element (2) and at least one seal gasket (3) rigidly secured to
said filter element, in which in order to form said gasket (3) a
plastic material is cast in the mould, and in order to rigidly
secure said filter element (2) to said gasket (3) in a sealed
manner the filter element is associated with said plastic material
while this is in said mould, characterised by being shaped in such
a manner as to form an accessory element (4) of the filter in order
to be able to remain removably associated with the filter even
after termination of curing of said plastic material.
17. A mould for forming an air filter (1, 5) comprising a filter
element (2) and at least one seal gasket (3) rigidly secured to
said filter element, in which in order to form said gasket (3) a
plastic material is cast in the mould, and in order to rigidly
secure said filter element (2) to said gasket (3) in a sealed
manner the filter element is associated with said plastic material
while this is in said mould, characterised by being shaped in such
a manner as to be able to be also used as at least a part of the
packaging (8) of the filter.
18. A mould for forming an air filter (1, 5) comprising a filter
element (2) and at least one seal gasket (3) rigidly secured to
said filter element, in which in order to form said gasket (3) a
plastic material is cast in the mould, and in order to rigidly
secure said filter element (2) to said gasket (3) in a sealed
manner the filter element is associated with said plastic material
while this is in said mould, characterised by being shaped in such
a manner as to be able to be also used as a filter holder (11) to
be directly associated with the device using the filter.
19. Packaging for an air filter of the type comprising a filter
element (2) and at least one seal gasket rigidly secured to said
filter element, in which in order to form said gasket (3) a plastic
material is cast in a mould (8), and in order to rigidly secure
said filter element (2) to said gasket (3) in a sealed manner the
filter element is associated with said plastic material while this
is in said mould; characterised in that said mould (8) is shaped in
such a manner as to be able to be also used as at least a part of
the packaging for the filter.
Description
[0001] The present invention relates to a method for forming an air
filter in accordance with the precharacterising part of the main
claim; the invention also relates to the filter obtained by this
method and the mould for implementing the method. To form known
filters, aluminium moulds are usually used presenting a first
recessed seat in which plastic material is cast to form the seal
gasket, and a second support seat for the filter element to which
said gasket is to be secured.
[0002] These moulds are usually closed by a backing mould for
impressing a desired shape on the upper part of the gasket, for
preventing undesired expansion of the plastic material during its
curing process, and for maintaining the filter element in a
predetermined position. To accelerate the curing time of the gasket
plastic material and to prevent the moulds remaining occupied for
too long a time, the moulds are heated, generally within a tunnel,
to accelerate the polymerization of the gasket plastic
material.
[0003] The mould then has to be opened, and the filter extracted
and trimmed to remove any burrs. Finally the filter has to be
packaged in suitable packaging for its sale. Before they can be
reused, the moulds also have to be treated with a separation agent,
a complication which further lengthens the production time of known
filters.
[0004] The production process for known filters is relatively
lengthy and for its implementation requires means which are
relatively complicated to control and use. An object of the present
invention is to provide a method for producing filters in
accordance with the precharacterising part of the main claim by
which the operations and the necessary equipment for producing the
filter are simplified.
[0005] A further object is to provide a filter forming method by
which the packaging and/or wrapping operations and/or the
installation of the filter are simplified. These and further
objects which will be apparent to an expert of the art are attained
by a filter forming method, a mould and a filter in accordance with
the characterising part of the independent claims.
[0006] The present invention will be more apparent from the
accompanying drawings, which are provided by way of non-limiting
example and in which:
[0007] FIG. 1 is a schematic perspective view of a first embodiment
of a mould according to the invention;
[0008] FIG. 2 is a schematic cross-section therethrough with a
filter inserted;
[0009] FIG. 3 is a schematic perspective view of a second
embodiment of a mould according to the invention, in the open
position;
[0010] FIG. 4 is a schematic cross-section therethrough in the
closed position;
[0011] FIG. 5 is a schematic cross-section therethrough with a
filter inserted;
[0012] FIGS. 6 and 7 are schematic cross-sections through a further
embodiment of a filter according to the invention.
[0013] To form an air filter 1 comprising a filter element 2 of
usual type and a seal gasket 3 rigidly secured to said gasket
element along the perimetral edge of the face 2A of said element, a
plastic material is cast in a mould 4 (FIGS. 1, 2). To rigidly
secure the filter element to the gasket in a sealed manner, the
filter element 2 is associated with the plastic material while this
is in the mould and is still only partially cured. According to the
invention, to form each filter a dedicated mould 4 is used and is
maintained removably associated with the gasket on termination of
the filter forming process. In this respect, according to the
invention the mould is advantageously constructed such as to enable
each filter to use its own dedicated mould, the mould being in this
manner a disposable mould (in the sense that it is not used again
for a further moulding operation) which can hence finally remain
associated with the filter after the filter forming process..
[0014] By virtue of the invention, the filter forming process is
much simplified, in that it is not longer necessary to provide
heating means for accelerating the mould plastic material curing
process, neither is it necessary to trim the gasket It is also no
longer necessary to transfer the moulds between the plastic
material filling stations, the curing stations and the filter
extraction stations, and to return the moulds to the filling
station when the filters have been formed. When filled with the
plastic material for the gasket and with the filter element, the
moulds of the invention can be simply stored or packaged without
having to force the plastic material curing process by thermal
treatment.
[0015] The method of the invention can be advantageously improved
by constructing the mould 5 such that it also forms the packaging
for the filter; in this manner the filter production process is
further accelerated by eliminating the filter packaging stage.
FIGS. 1 and 2 show a first embodiment of a mould according to the
invention, comprising a recessed surround 6 into which to pour the
plastic material for forming the filter gasket 3, and a flat
support surface 7 for the filter element 2. The flat surface 2 is
provided inwards of said surround at a lower height than the free
edge 6A of the recessed surround 6 and its dimensions are less than
those of the face 2A of the filter element 2, so that the plastic
material can surround a perimetral portion T of the element 2 at
said face 2A.
[0016] The mould of the invention is formed of any material which
allows easy detachment of the plastic material used to form the
gasket 3 but which ensures that the shape of the mould is
maintained during the infeed and curing of the gasket plastic
material within the recessed surround 6.
[0017] Advantageously the plastic materials for forming the mould
and the gasket are mutually incompatible, that is plastic materials
having characteristics such that they cannot merge with each other
during the curing of the plastic material with which the gasket is
formed, and consequently extraction of the filter from the mould
does not prove difficult.
[0018] The mould can for example be formed of polystyrene,
polypropylene, polyethylene, teflon or mixtures of these plastic
materials, or of polyethylene-clad paper. The gasket can for
example be formed of a plastic polymer, preferably polyurethane.
Crosslinked or non-crosslinked thermosetting polymers such as
polyurethanes can for example be used. Polyurethane polymers can,
for example, be used having a density variable between 0.1 Kg/l and
2 Kg/l.
[0019] FIGS. 3-5 show a variant of the already illustrated mould,
in which in contrast to the already described embodiment the mould
8 in which the plastic material is cast also has a backing mould or
cover 9.
[0020] The purpose of this cover is to upperly close the mould in
order to limit growth of the plastic material during its curing
while at the same time compelling it to assume a desired shape, so
that the gasket 3 upperly presents a particular form. At the same
time the cover 9 is able to maintain the filter element 2 in its
correct position during the curing of the plastic material, for
which purpose it presents a seat 9D shaped to house the filter
element 2 as an exact fit.
[0021] The cover 9 can be constructed in one piece with the mould 8
or can be secured to it in known manner (for example by bonding or
gluing or insertion-fitting) once the gasket plastic material has
been poured in and the filter element positioned. Advantageously,
the cover 9 and the mould 8 present flat edge faces 8A and 9A which
make contact with each other when the two parts are superposed,
hence facilitating the joining of the two parts. This covered mould
can also be formed of the same materials described with reference
to the already described mould 4.
[0022] The covered mould can also advantageously be used as the
filter packaging or wrapping for its marketing. For this purpose
the flat edge faces 8A, 9A can also for example comprise enlarged
elements 8B, 9B and/or holes 8C/9C or other usual expedients to
facilitate the fixing of the package to a display unit and/or for
applying labels. If used as packaging, the mould 5 can also
comprise additional outer walls 15 (shown by dashed lines in FIG.
4), to give the mould a more pleasant appearance. If used as
packaging, the cover 9 and mould 8 can be rigidly secured together
once the plastic material has been poured into the mould 8 and the
filter element 2 has been positioned.
[0023] In a further embodiment shown in FIGS. 6, 7, the mould of
the invention is shaped in such a manner as to also act as a filter
holder to enable the filter to be directly associated with the
device which uses the filter. In this variant, the mould 11
presents not only the characteristics described with reference to
the aforegoing moulds, but also further usual elements for
connecting the filter to the device which uses the filter. For
example, at at least one aperture or hole 10A corresponding in
position with the face 2A of the filter element 2, the mould 11
also presents a nozzle 10 to be inserted into a usual filtered air
entry seat of a usual device using the filter (not shown). Likewise
the cover 12 presents at least one aperture or hole 13 for passage
of the air to be filtered. The cover 12 and mould 11 are associated
with each other, for example by resilient clips 14 provided on the
flat edge faces 11A, 12A.
[0024] By virtue of the embodiment according to this variant, the
filter can be directly associated with the device requiring the
filter without having to be mounted in the relative filter holder
of that device.
[0025] Finally it should be noted that the aforedescribed
embodiments are provided by way of example only, and that numerous
variants are possible, all falling within the same inventive
concept. For example, the mould and/or the cover could be provided
with further seats for also forming a seal gasket along another
face of the filter element 2 and/or the gasket 3 could be provided
in a different position of the filter element
* * * * *